近年来,我国肉类加工行业发展迅猛,自动化和智能化水平逐渐提高,多种肥瘦比例检测技术被应用到肉制品加工和屠宰行业。双能X射线吸收法(dual energy X-ray absorptiometry,DXA)是解决肉制品在线肥瘦比例检测的最佳方法之一,具有精准度...近年来,我国肉类加工行业发展迅猛,自动化和智能化水平逐渐提高,多种肥瘦比例检测技术被应用到肉制品加工和屠宰行业。双能X射线吸收法(dual energy X-ray absorptiometry,DXA)是解决肉制品在线肥瘦比例检测的最佳方法之一,具有精准度高、耗时短、可以对胴体全身进行检测的优势。本文比较当前各种肥瘦比例检测技术的特点,介绍DXA的概念、测量方式,重点探讨DXA在肥瘦比例测定中的应用和研究进展,通过对研究现状、设备类型和存在问题的分析,讨论未来该技术应用的发展方向。展开更多
目的探讨采用双源CT双能量心脏扫描模式在运动负荷状态下分析患者冠状动脉血流的可行性。方法对18例临床可疑冠心病患者进行双能量冠状动脉血管成像,所有患者被分为2组,其中进行运动负荷扫描的患者10例,静息进行扫描的患者8例。所有双...目的探讨采用双源CT双能量心脏扫描模式在运动负荷状态下分析患者冠状动脉血流的可行性。方法对18例临床可疑冠心病患者进行双能量冠状动脉血管成像,所有患者被分为2组,其中进行运动负荷扫描的患者10例,静息进行扫描的患者8例。所有双能量数据被传至工作站进行双能量重建,重建序列包括碘图序列和融合120 k V序列。分别在碘图序列和融合120 k V序列测量冠状动脉各支近端、中段和远端的强化值和主动脉根部强化值,以此计算冠状动脉强化比率(CER),并比较两组的差异性。结果所有患者以冠状动脉的狭窄程度>50%和心肌负荷显像显示心肌缺血的患者被进行分层。碘图所测的狭窄程度>50%和心肌负荷显像显示心肌缺血的患者CER分别为0.77±0.05和0.76±0.05,明显低于狭窄<50%和无心肌缺血的患者CER分别为1.05±0.35和0.99±0.31,P<0.05。而融合120 k V图像两组比较没有差异性。结论碘图CER是一种可选的方法评估冠状动脉狭窄和心肌缺血。展开更多
This study delves into the combustion behavior of various lignite types within a circulating fluidized bed boiler(CFBB),with a primary focus on the impact of different bed material sphericity ratios(0.5,0.7,and 0.9).U...This study delves into the combustion behavior of various lignite types within a circulating fluidized bed boiler(CFBB),with a primary focus on the impact of different bed material sphericity ratios(0.5,0.7,and 0.9).Utilizing bed material with a sphericity ratio of 0.9 sourced from theÇan power plant and verified through experimentation,the research reveals several key findings.Notably,furnace temperatures tended to rise with higher sphericity ratios,albeit with variations between lignite types,particularly highlighting the complexity of this relationship in the case of GLI-Tunçbilek lignite.Pressure levels in the combustion chamber remained consistent across different sphericity ratios,indicating minimal influence on pressure dynamics.Improved combustion efficiency,especially at the bottom of the boiler,was observed at lower sphericity levels(0.5 and 0.7)forÇan lignite,as reflected in CO_(2) mole fractions.While NO_(x) emissions generally decreased with lower sphericity,the sensitivity to sphericity varied by lignite type,with Ilgın lignite showcasing low NO_(x) but high SO_(2) emissions,underscoring the intricate interplay between lignite properties,sphericity,and emissions.Overall,this study advances our understanding of CFBB combustion dynamics,offering insights valuable for optimizing performance and emissions control,particularly in lignite-based power.展开更多
文摘近年来,我国肉类加工行业发展迅猛,自动化和智能化水平逐渐提高,多种肥瘦比例检测技术被应用到肉制品加工和屠宰行业。双能X射线吸收法(dual energy X-ray absorptiometry,DXA)是解决肉制品在线肥瘦比例检测的最佳方法之一,具有精准度高、耗时短、可以对胴体全身进行检测的优势。本文比较当前各种肥瘦比例检测技术的特点,介绍DXA的概念、测量方式,重点探讨DXA在肥瘦比例测定中的应用和研究进展,通过对研究现状、设备类型和存在问题的分析,讨论未来该技术应用的发展方向。
文摘目的探讨采用双源CT双能量心脏扫描模式在运动负荷状态下分析患者冠状动脉血流的可行性。方法对18例临床可疑冠心病患者进行双能量冠状动脉血管成像,所有患者被分为2组,其中进行运动负荷扫描的患者10例,静息进行扫描的患者8例。所有双能量数据被传至工作站进行双能量重建,重建序列包括碘图序列和融合120 k V序列。分别在碘图序列和融合120 k V序列测量冠状动脉各支近端、中段和远端的强化值和主动脉根部强化值,以此计算冠状动脉强化比率(CER),并比较两组的差异性。结果所有患者以冠状动脉的狭窄程度>50%和心肌负荷显像显示心肌缺血的患者被进行分层。碘图所测的狭窄程度>50%和心肌负荷显像显示心肌缺血的患者CER分别为0.77±0.05和0.76±0.05,明显低于狭窄<50%和无心肌缺血的患者CER分别为1.05±0.35和0.99±0.31,P<0.05。而融合120 k V图像两组比较没有差异性。结论碘图CER是一种可选的方法评估冠状动脉狭窄和心肌缺血。
文摘This study delves into the combustion behavior of various lignite types within a circulating fluidized bed boiler(CFBB),with a primary focus on the impact of different bed material sphericity ratios(0.5,0.7,and 0.9).Utilizing bed material with a sphericity ratio of 0.9 sourced from theÇan power plant and verified through experimentation,the research reveals several key findings.Notably,furnace temperatures tended to rise with higher sphericity ratios,albeit with variations between lignite types,particularly highlighting the complexity of this relationship in the case of GLI-Tunçbilek lignite.Pressure levels in the combustion chamber remained consistent across different sphericity ratios,indicating minimal influence on pressure dynamics.Improved combustion efficiency,especially at the bottom of the boiler,was observed at lower sphericity levels(0.5 and 0.7)forÇan lignite,as reflected in CO_(2) mole fractions.While NO_(x) emissions generally decreased with lower sphericity,the sensitivity to sphericity varied by lignite type,with Ilgın lignite showcasing low NO_(x) but high SO_(2) emissions,underscoring the intricate interplay between lignite properties,sphericity,and emissions.Overall,this study advances our understanding of CFBB combustion dynamics,offering insights valuable for optimizing performance and emissions control,particularly in lignite-based power.